Memory foam mattress system

ABSTRACT

A memory foam mattress system includes a viscoelastic mattress, a slat-type mattress support, and a viscoelastic pillow. The mattress includes a viscoelastic top layer atop a denser foam core layer, surrounded by a removable cover. The viscoelastic foam material is configured to provide a substantially uniform viscoelastic response over a room temperature range of from about 55° F. to about 85° F. The mattress support includes a perimeter frame with a plurality of transverse slats spanning the frame, including seven adjustable pairs of slats, with a support slat under each adjustable pair. A moveable adjustment clip attaches each support slat to a corresponding adjustable pair, to allow adjustment of the stiffness of the adjustable pair. The pillow has a body of viscoelastic foam with a contoured top and a flat bottom, surrounded by a cover. The contoured top has two support ridges, a larger one for side sleeping, and a smaller one for back sleeping. Foam inserts of varying densities are disposable in insert pockets in each ridge to adjust the firmness of the ridges.

[0001] The present application claims priority from the following U.S.provisional patent applications: Ser. No. 06/390,982; Ser. No.60/390,984; and Ser. No. 60/390,985, all filed on Jun. 22, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to mattresses. Moreparticularly, the present invention relates to a mattress systemincluding a viscoelastic foam mattress, an adjustable slat-type mattresssupport system, and an adjustable density viscoelastic foam pillow.

[0004] 2. Related Art

[0005] It is estimated that over 100 million Americans aresleep-deprived. New research shows that sleep is the third essentialcomponent, combined with good diet and regular exercise, for a long andhealthy life. Recent clinical sleep studies and research findingsindicate disturbing dangers for people who short-change their dailysleep needs even a little. Sleep debt could be a factor in the nationalepidemics of obesity and diabetes. The lack of sleep reduces growthhormone secretion, which controls the body's proportions of fat andmuscle, accelerating fatty weight gains. In a 1999 University of Chicagosleep study, healthy young men with no other risk factors developed to apre-diabetic state after getting four hours of sleep per night for justone week.

[0006] Inadequate sleep can also weaken immune systems. Human studiesshow that inadequate sleep changes white blood cell counts and immuneresponse modifiers—biological evidence that the body is having troublefighting infection. Recent sleep deprivation studies have found thatpeople with less sleep scored lower on tests of judgment, response time,attention, and had more mistakes than those who slept 8 hours. Abouthalf of the sleep-deprived subjects were having uncontrolled sleepattacks, in which they could not stay awake. The National SleepFoundation attributes about 100,000 highway crashes a year to sleepdeprivation. This results in an enormous loss of productivity at work asindividuals struggle to remain awake. In their personal lives, lack ofadequate sleep also causes increased irritability, which can place asignificant strain on interpersonal relationships, especially maritaland family relationships, as well as between friends, acquaintances, andcoworkers.

[0007] The most often-reported cause of sleep deprivation is anuncomfortable mattress. Traditional bedding systems incorporate amattress consisting of an outer layer of fabric and foam padding,surrounding a series of spring coils. The fabric is stretched tightlyacross the foam to hold it in place, which in most cases creates asurface that is too hard. The mattress is usually supported by aflexible box spring to allow the mattress to compress where needed.However, the stiffness of the box springs causes it to push back againstthe mattress in the areas of greatest compression, usually the regionsof the shoulders and hips. When the shoulders and hips do not sink intothe mattress sufficiently, there is inadequate support for the spine,causing it to bend downward towards the mattress.

[0008] It is becoming increasingly clear that conventional mattress andbox spring systems are not healthy. A standard flat mattress puts higherpressure on shoulders, hips, and thighs, which constricts the veins anddisrupts cell function. Heart rate increases, the heart pumps harder tokeep blood flowing, causing blood pressure to climb, thereby stressingthe body. Major studies show that pressure becomes unhealthy at levelsover 40 mmHg (millimeters of mercury). Standard U.S. major brandedmattresses put an average of 56 mmHg on weight bearing surfaces of thebody. Side sleeping can place 61 mmHg pressure on the hip alone. Thiswill cause a person to toss and turn up to 200 times a night as opposedto 20 to 40 times. The more restless a body is, the less rest it willget.

[0009] Studies also show that traditional mattresses and box springs cantwist the spine by resisting the weight of the shoulders and hips,resulting in two negative consequences. First, poor support contorts theback and body, resulting in bone and muscle stress, increasingdiscomfort, and interrupting sleep patterns. Second, this createspressure points that impair circulation, which increase heart rate andblood pressure. These changes combined with the discomfort from thepressure points results in poor sleep.

[0010] The human spine at rest has a different shape depending on theorientation from which it is viewed. Viewed from the back, the spineshould appear essentially straight. Viewed from the side, the spine hasan S-curved shape. When the spine is bent out of its natural orientationfor long periods of time, the result is back pain and discomfort. Mostpeople sleep on conventional mattresses that have a tendency to do justthat—contorting their spines out of the comfortable range every night,producing symptoms ranging from mild discomfort to severe back pain. Foran individual lying on their side, this causes the spine to bendlaterally out of the preferred orientation, thus curving the normallystraight spine as seen from the back. For an individual lying on theirback, this causes the spine to sag downwards out of the preferredorientation, thus straightening the normally curved spine, particularlytoward the small of the back, as seen from the side.

[0011] Changing the stiffness and the number of spring coils in themattress can alleviate this problem to some degree. However, the optimalstiffness of the coils should be different depending on body type andweight. Traditionally, U.S. bedding manufacturers tend to ignore bodytypes and weight, and market sleep systems constructed under theinaccurate assumption that 95% of the population has the same body type.

[0012] One attempt to provide a mattress that can contour itself to theshape of the body in such a way as to keep the spine in a more neutralalignment uses a mattress consisting of a soft core layer ofpolyurethane foam, topped with a layer of viscoelastic foam. An exampleof this type of construction is the Tempur-Pedic® mattress. Viscoelasticfoam is an open-celled material that is temperature and weightsensitive, becoming more soft and pliable with increases in temperature.Viscoelastic foam conforms to the body shape due to a combination ofweight distribution and the increase in temperature associated with bodycontact. As the position of the body changes, the viscoelastic foamadjusts to the resulting shape. It is thought that because theviscoelastic material compresses to a greater extent in areas around theshoulders and hips where body temperature and weight are the highest,the spine will be supported, thus decreasing back pain. In reality, alarge number of these mattresses are routinely returned to their sellersbecause they actually cause increased discomfort and back pain,suggesting that they do not support the spine in the optimal positionwhen a user is lying on their side or back.

[0013] Another possible approach to providing better sleep support is tomodify the box spring. One such approach is to use a slat-type mattresssupport instead of a box spring. This type of mattress support utilizesa system of transverse wooden slats attached across a perimeter frame,upon which the mattress sits. Some of these slat-type systems includemultiple pairs of slats attached to the frame, with some of the pairsbeing adjustable. The adjustable pairs of slats correspond to variousregions of the body from the knees to the middle of the back. Oneproblem with prior slat systems pertains to individuals with unusualbody proportions, such as a person with very large shoulders or a personwith a very small waist and wide hips. There is generally not enoughflexibility or adjustability in the slats of prior systems toaccommodate these people. Similarly, existing slat systems generally donot provide adjustability for the shoulders, a region of the body thatis important in maintaining proper spinal alignment.

[0014] The range of motion of the neck also makes it very susceptible toharm, including harm from an improper sleeping position. Slouchingwithout proper support can triple the weight load on the neck, oftencausing soreness, stiffness, and eventually pain throughout the night.Soreness, stiffness and pain are body signals that harm is being done tothe upper spine. This hinders sleep patterns, resulting in morningfatigue, headaches, and stiffness of the neck and shoulders, andeventually possible spinal disc damage.

[0015] Traditional rectangular pillows, consisting of an outer layer offabric or plastic surrounding a soft core of feathers, soft foam pieces,or other similar material, tend to lose their ability to support thehead and neck soon after a body lies on them. To compensate, sleepersfrequently place their arm under their pillow or head while sleeping tomake up for lost support. Sleeping in this position “shrugs” theshoulders up. To compensate, the sleeper, is forced to round their back,stressing the back and neck, making pain in the morning more likely.

[0016] Depending on the core material, these pillows can have a widerange of compressible and elastic properties. Pillows made from feathersor down are softer and compress more easily, thus providing little or nosupport to the cervical curve, a property that worsens over time withuse. Pillows with foam chips are very elastic, but do not compress asreadily. When lying on one's back, the head will tend to be rotated toofar forward, relative to the spine, with a foam core pillow, and too farback with a feather pillow. When lying on one's side, the head will tendto be rotated toward the bed with a soft feather core pillow, and awayfrom the bed with a foam core pillow. The result of both of thesesituations is that the head is rotated out of its optimal cervicalalignment with the spine, thus placing strain on the neck, creating anuncomfortable sleep environment and eventually damaging the cervicalcurve of the neck.

[0017] Another important issue related to head and neck support concernsthe asymmetries associated with lying in the different positions.Because of the shape and orientation of the head relative to theshoulders, the area required for optimal support while lying on the sideis different from what is required when lying on the back. In otherwords, the curvature and space under the back of the head and neck whenlying on one's back are small compared to the corresponding distancefrom the end of the shoulder to the underside of the head and neck whenlying on one's side.

[0018] One attempt to solve this problem provides a pillow with acontoured top. Such pillows have asymmetrical, semicylindrical ridges ina contoured top, a large one for lying on the side, and a smaller onefor lying on the back. Some pillows of this type are made fromviscoelastic or “memory” foam, surrounded by a cover material. Theviscoelastic foam conforms to the head and neck shape due to acombination of weight distribution and the increase in temperatureassociated with body contact. As the position of the head and neckchanges, the viscoelastic foam adjusts to the resulting shape. It isthought that the combined effects of the contoured ridges and theshape-conforming properties of the viscoelastic foam would provide goodsupport for the head and neck, thus maintaining neck-spine alignment. Itis hoped that this would decrease neck discomfort and allow a morecomfortable and restful sleep.

[0019] In reality these pillows do not adequately support the head andneck for different body shapes, such as broader shoulders, resulting inincreased neck discomfort for different body shapes. Also, as theviscoelastic foam conforms to the head and neck, it begins to trap bodyheat. This makes the foam more pliable, causing the head and neck tocontinue to sink into the pillow, ultimately reducing support for thecervical curve, similar to a feather core pillow. In addition, mostviscoelastic foam contour pillows in the market are affected by roomtemperature, which can adversely affect the hardness of the pillow,particularly as temperature decreases. This can create pressure pointsthat can result in contortion of the neck and additional neck pain.

OBJECTS AND SUMMARY OF THE INVENTION

[0020] It is therefore an object of the present invention to provide amattress system that keeps the spine properly supported regardless ofthe body shape or weight of the user.

[0021] Another object of the invention is to provide a mattress systemthat allows the spine to remain in a more neutral position for both sideand back sleepers.

[0022] Another object of the invention is to provide a mattress systemthat is adjustable for individual body shapes, reduces blood circulationrestriction, minimizes the telegraphing of motion, and reduces pressurepoints on the shoulders and hips.

[0023] Another object of the present invention is to provide a mattressand/or pillow that is not significantly affected by the surrounding roomtemperature.

[0024] An object of the present invention is to provide a pillow thatadequately supports the head and neck when lying on the back or theside.

[0025] Another object of the present invention is to provide a pillowwith adjustable firmness for different body shapes.

[0026] In accordance with one aspect thereof, the invention provides amattress system, comprising a mattress, including a core layer providinga base support, and a top layer of viscoelastic foam, disposed atop thecore layer, having a density of from about 3.0 to about 4.5 lb/ft³.

[0027] In accordance with a more detailed embodiment thereof, the corelayer may comprise foam material having a density of from about 2.5 toabout 2.7 lb/ft³.

[0028] In accordance with another aspect thereof, the invention providesa mattress, comprising a core layer of foam material, having a coredensity primarily configured to support a human body, and a top layer ofviscoelastic foam, disposed atop the core layer. The top layer has acomposition that maintains substantially uniform viscoelastic responseover a room temperature range of from about 55° F. to about 85° F.

[0029] In another embodiment, the invention provides a mattress supportsystem, comprising a perimeter frame, with a plurality of pairs of slatsspanning the width of the frame and attached to the frame by suspensionclips. The plurality of pairs of slats include nonadjustable pairs andadjustable pairs. A support slat is disposed beneath each pair ofadjustable slats. A total of 7 pairs of adjustable slats span theregions from the shoulder to the knees of an individual lying on amattress atop the mattress support. Each stiffener slat is connected toa corresponding adjustable pair of slats by an adjustment clip, suchthat sliding the adjustment clip along the length of the adjustable pairof slats changes the stiffness of the adjustable pair of slats, therebyadjusting the stiffness of the mattress support in each of seven regionsbetween the shoulders and hips.

[0030] In accordance with another aspect thereof, the invention providesa pillow, comprising a viscoelastic foam body with a contoured top and aflat bottom. Advantageously, the viscoelastic foam material isconfigured to provide a substantially uniform viscoelastic response overa room temperature range of from about 55° F. to about 85° F. Thecontoured top has two support ridges, a large one for supporting thehead and neck when lying on one's side, and a small one for supportingthe head and small of the neck when lying on one's back. Within thesupport ridges are two insert pockets. Foam inserts are disposed in theinsert pockets, so as to support the viscoelastic foam in the supportridges. Different density foam inserts can be disposed into the insertpockets to adjust the firmness. The viscoelastic foam and the insertsare surrounded by a cover with an opening to access the inserts.

[0031] Additional features and advantages of the invention will beapparent from the detailed description which follows, taken inconjunction with the accompanying drawings, which together illustrate,by way of example, features of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032]FIG. 1 is a cross-sectional view of a memory foam mattress inaccordance with an embodiment of the present invention.

[0033]FIG. 2 is a perspective view of a mattress support system inaccordance with an embodiment of the present invention.

[0034]FIG. 3 is a cross-sectional view of the mattress support systemwith a viscoelastic mattress in accordance with an embodiment of thepresent invention.

[0035]FIG. 4 is a cross-sectional view of a pair of adjustable slats, astiffener slat and an adjustment clip.

[0036]FIG. 5 is a side view of an individual lying on a viscoelasticmattress and mattress support.

[0037]FIG. 6 is a perspective view of a pillow in accordance with anembodiment of the present invention;

[0038]FIG. 7 is a cross-sectional view of the pillow of FIG. 1;

[0039]FIG. 8 shows a perspective view of the spine curvature for aperson lying on their back; and

[0040]FIG. 9 shows a perspective view of the spine for a person lying ontheir side.

DETAILED DESCRIPTION

[0041] Reference will now be made to the exemplary embodimentsillustrated in the drawings, and specific language will be used hereinto describe the same. It will nevertheless be understood that nolimitation of the scope of the invention is thereby intended.Alterations and further modifications of the inventive featuresillustrated herein, and additional applications of the principles of theinventions as illustrated herein, which would occur to one skilled inthe relevant art and having possession of this disclosure, are to beconsidered within the scope of the invention.

[0042] One of the major problems in the prior art concerns the tendencyfor a viscoelastic mattress to allow the spine to sag downward.Viscoelastic foam mattresses typically use a soft polyurethane corelayer having a density of about 1.8 lb/ft³, to support a 5 lb/ft³viscoelastic layer, It is thought that this combination of materials canadequately support the spine, create comfortable sleeping conditions,and decrease the occurrence of mattress-related back pain. In reality,the inventors believe that the combination of a relatively soft corelayer with a relatively dense viscoelastic layer actually causesincreased discomfort and back pain, because it does not adequatelysupport the spine. The lack of support causes the spine to straighten(as seen from the side) from its naturally curved shape when anindividual lies on their back, or to curve (as seen from the back) fromits naturally straight shape when the individual lies on their side.

[0043] This problem is compounded by the temperature sensitivity of thetop layer of viscoelastic material. As the shoulders and hips press downthey trap heat in the layer. This increase in temperature causes thematerial to become softer, thus causing even greater compression. Inaddition to compounding the crooked spine problem, the increased heatcan become uncomfortable and interrupt sleep.

[0044] To address these problems, most makers of viscoelastic foammattresses have gone to a denser viscoelastic foam top with a softerpolyurethane core. The inventors believe this approach is the oppositeof what is needed. To address some of the failings of prior mattresses,the inventors have invented a mattress comprising a core layer with agreater density than the prior art, combined with a viscoelastic toplayer with a lower density than the prior art.

[0045] As shown in FIG. 1, the present invention provides a mattress 10comprising a top layer of viscoelastic foam 12, and a core layer 14. Thepreferred viscoelastic foam layer ranges in density from about 3 toabout 4.5 lb/ft³ and can be from about 2 to about 4 inches thick. In oneembodiment of the invention, the viscoelastic foam layer is about 4lb/ft³ in density and is about 3″ thick. A suitable material havingthese properties is the 3510 viscoelastic foam available from DomfoamInternational, Inc. of Quebec, Canada. This material has a density thattypically ranges from about 3.5 to 4.0 lb/ft³. The core layer ispreferably polyurethane foam, about 3 to 7 inches thick, with a densityof about 2.5±5% lb/ft³ (2.3 to 2.7 lb/ft³), or any other material ormaterial combination with similar compression properties. For example,the core layer can be polyurethane foam, latex foam, or a combination ofpolyurethane and latex foams. Additionally, spring coils, a honeycombspring structure, or any other material providing similar supportcharacteristics could be used for the core layer. In one embodiment, thecore layer consists of about a 5″ layer of high resilient polyurethanefoam with a density of about 2.5 lbs/ft³. The viscoelastic layer 12 andthe core layer 14 are attached together with a chemical adhesive, suchas a clean hot melt glue, and surrounded by a cover 16 to protect themattress. Other adhesives could also be used, such as water based glues,latex bases glues, and ethylene chloride based glues. The cover isremovable, and includes a zipper 18 for allowing removal from themattress, such as to facilitate washing, etc. In one embodiment, thecover is quilted terry cloth made of a cotton/polyester blend.Alternatively, the cover could be made of cotton stretch fabric. It willbe apparent that quilting is optional. Moreover, the cover could bepermanently attached to the mattress, such as by sewing or with anadhesive, rather than being removable. The cover can also include suchadditions as an anti-microbial treatment and a breathable liquid barrierinner lining.

[0046] The lower density viscoelastic layer compresses to a greaterextent than the higher density viscoelastic foam of the prior art. Thiseffect, coupled with the reduced compressibility of the denserpolyurethane core layer, provides greater spine support as the shouldersand hips sink into the combination of materials. This results in thespine being supported more closely to its optimally curved orientationwhen lying on the back, and its optimally laterally straight orientationwhen lying on the side. In addition, the lower density viscoelastic foamis not as affected by temperatures in the range of the body.

[0047] One common problem of viscoelastic mattresses is the sensitivityof the mattress to the surrounding ambient temperature. With otherviscoelastic materials, the mattress is more sensitive to temperaturechanges. The colder the room temperature, the harder the mattressbecomes. For example, other viscoelastic mattresses become quite hardand unpliable at temperatures at or below about 65° F. Indeed, attemperatures below about 50° F. the denser viscoelastic foam of theTempur-Pedic® mattress can actually break if one attempts to bend it. Asanother example, Serta produces a mattress with a viscoelastic foamhaving a density of about 2.5 lb/ft³ that becomes noticeably hard attemperatures below 65° F. Consequently, some producers of thesemattresses insist that the user must maintain a specific roomtemperature (e.g. 71° F.) for the mattress to function properly.

[0048] Advantageously, the firmness and consistency of the mattress ofthe present invention is more consistent over a wider variety oftemperatures, providing a more consistent level of support and comfort,regardless of room temperature. Specifically, the inventors have foundthat the 3510 viscoelastic foam mentioned above remains substantiallymoldable and pliable at temperatures as low as 30° F., and starts tobecome noticeably former at temperatures close to 0° F. and below. Moreparticularly, this foam material has a density that is preferably in therange of from about 3.5 to about 3.8 lb/ft³ (though the density can varyup to about 4 lb/ft³), and exhibits an indentation deflection force(IDF) of 10±3 (i.e. an IDF range of 7-13). Indentation deflection forceis a standard measure used in the foam industry to measure the strengthof foam materials. The IDF measures the pressure (e.g. in psi) requiredto depress and hold a flat metal plate of a standard size (e.g. 12″square) a certain distance (e.g. ½″) into the surface of a foammaterial. The inventors have found that for the 3510 viscoealstic foamthe variation in IDF over a temperature range of from about 30° F. to100° F. is less than about 15%. Within the range of typical roomtemperatures (e.g. from about 60° F. to about 85° F.) the variation ismuch less. Thus, within the range of likely room temperatures, themoldability and viscoelastic response of the present mattress issubstantially constant, and any variation over this temperature range issubstantially unnoticeable to an ordinary user.

[0049] The temperature insensitivity of this viscoelastic material wasan unexpected result. Specifically, this viscoelastic material wasapparently not developed with the intent of reducing temperaturesensitivity. The producers of the material did not recognize thisproperty, and did not recognize its suitability to bedding applications.However, after selecting this material for use in the invention, theinventors discovered this property and recognized its advantages.

[0050] People with back trouble fall along a continuum from milddiscomfort to severe back pain. Those individuals that have severe backproblems have a very difficult time finding a comfortable mattress. Withthe mattress of the present invention, the inventors have found thatmost individuals with severe back problems that tried the mattressexperienced improved sleeping. What was surprising, however, was thatthis mattress also helped others to sleep better, not just those withback problems.

[0051] There are a variety of different types of mattress supportsystems, including platform systems, box springs, electric adjustableframes, and slat-type supports. Conventional mattresses are not equallycompatible with each of these types of systems, and present variousdrawbacks when used with each of them, such as producing pressure pointsand contorting the spine. Advantageously, the viscoelastic mattressdisclosed above is compatible with all of these types of systems byreducing pressure points and giving greater support for the spine. Forgreater support and adjustability, the present invention advantageouslyprovides an improved adjustable slat-type mattress support system.Traditional slat support systems generally do not provide a region ofadjustability to differentially support the shoulders. Additionally,individuals with extreme body proportions may derive little benefit fromconventional slat systems because the range of adjustability of theslats may not encompass a range including their body type.Advantageously, the inventors have developed a bedding system thatprovides adequate adjustability to support the shoulders, and anincreased range of flexibility to allow adequate alignment of the spinefor those individuals with extreme body proportions.

[0052] Typical adjustable slat support systems incorporate up to 6 pairsof adjustable slats, corresponding to regions of the body from thethighs to the upper region of the back. A stiffener slat is disposedbeneath each of the adjustable pairs and attached by a pair of adjustorclips. The adjustor clips can be slid from one end of the adjustablepair to the other to alter the stiffness of the slats in that region.When the adjustor clips are at opposite ends of the slats (i.e. towardthe perimeter frame), the stiffener slat has little effect on theadjustable pair. As the adjustor clips are moved toward the center, theadjustable pair of slats is increasingly stiffened due to the addedsupport of the stiffener slat. As a result, the overlying mattress willhave areas of differential support that can be adjusted to match theweight distribution and shape of an individual.

[0053] Unfortunately, typical slat-type support systems do not provideadjustability for the shoulders. The inventors have discovered that amattress support with a 7^(th) pair of adjustable slats positioned underthe shoulders improves spinal support. Further, the inventors havediscovered that using a viscoelastic foam mattress, such as thatdescribed above, atop this mattress support provides a combination ofthe differential flexibility of the slats and the body conformingproperties of the viscoelastic mattress. This creates a bedding systemthat provides better support and comfort for many individuals, includingthose with extreme body proportions or back trouble. By replacing theuniform stiffness of box springs with a system that is capable ofproviding varying degrees of support to critical pressure zones of theneck, shoulders, chest, waist, hips and knees, pressure is more evenlydistributed and the stressors that disturb sleep are reduced.

[0054] In one embodiment shown in FIG. 2, the invention provides aslat-type mattress support 20 having a perimeter frame 22 and aplurality of slats, including nonadjustable slats 24 and adjustableslats 26, spanning the width of the frame. The slats are attached to theframe (singly or in pairs) by resilient connectors (31 in FIG. 3), suchas suspension clips. The suspension clips allow the slats to move downand rotate slightly in response to weight from above. In the embodimentshown in FIG. 2 there are approximately 13 pairs of slats, though exactnumber may vary, particularly for tall individuals (e.g. those over 6′3″tall). The adjustable slats include 6 pairs of middle adjustable slats29 (positioned from the knees to the middle of the back) and a seventhpair of shoulder support slats 27. One stiffener slat 32 is disposedbeneath each of the seven pairs of “adjustable” slats corresponding toregions of the body from the knees to the shoulders.

[0055] The stiffener slats 32 are each attached to a correspondingadjustable pair of slats 26 with an adjustment clip 28. FIG. 3 shows theorientation of the stiffener slat 32 in a side view, and FIG. 4 showsits orientation in a cross-sectional view. The location of theadjustment clips 28 relative to the ends of the adjustable pair of slatsdetermines the flexibility of that region of the mattress supportsystem. When the adjustment clips are located near the outer edges ofthe perimeter frame, the adjustable slats are more flexible. When theadjustment clips are located near the middle, the adjustable slats aremore stiff, due to the added support of the stiffener slat. FIG. 4 showsa cross-sectional view of an adjustable pair of slats 26, a stiffenerslat 32, and the adjustment clip 28. Also shown is a nonadjustable slat34. The stiffness of the nonadjustable slats remains constant, while thestiffness of the adjustable slats is augmented by the adjustment clips,which press against the stiffener slat.

[0056] When an individual uses this mattress support system 20, thedegree of support of the mattress can be selectively adjusted to suitthe body shape and weight distribution of that individual. For bed sizeslarge enough to sleep two individuals, each side may be adjustedindependently, to provide the ideal spinal support for each user. Inthis embodiment of the invention, a center support 30 longitudinallybisects the perimeter frame 22 into two functional mattress supports,each with its own set of slats 24, 26 and adjustment clips 28.

[0057] One great advantage of this slat-type support system 20 is theability to fine-tune the slat configuration to further accommodatephysical alterations due to changes in weight and health. Compared tothe unforgiving stiffness of a box spring or platform foundation, theslat suspension system has greater ability to respond specifically toevery contour and weight. It substantially reduces the problems of sag,motion, or rollover found in conventional mattress/box springcombinations.

[0058] Different types of mattresses may be used with this mattresssupport system 20. However, it will be apparent that different types ofmattresses will interact differently with the mattress support. One typeof mattress that appears to work well with this mattress support systemis a viscoelastic foam mattress as described above. As shown in FIG. 3,the viscoelastic mattress 40 comprises a top layer 42 of viscoelasticfoam, and a core layer 44. These layers can be configured as discussedabove. The viscoelastic layer 42 and the core layer 44 are attachedtogether with a chemical adhesive and surrounded by a cover 46 toprotect the mattress. The cover contains a zipper 48 for its removalfrom the mattress.

[0059] Shown in FIG. 5 is a cross-sectional view of an individual 52lying on the bedding system 50. The viscoelastic mattress 40 compressesin response to the weight of the body, especially around the shouldersand hips when the person is lying on tier side. Similar compressionoccurs when the person is lying on their back. As shown, the slat-typemattress support 20 has been fine-tuned to deflect downwards in areaswhere the compression of the mattress is greatest, due to the downwarddeflection and rotation of the adjustable slats 16. This allows an evengreater degree of flexibility around the shoulders and hips,complimenting the body-conforming and supporting properties of theviscoelastic mattress.

[0060] A bedding system composed of an adjustable slat-type mattresssupport and a body conforming viscoelastic mattress can be a greatbenefit not only to those with extreme body proportions, but also topeople with mild to severe back pain. For example, people with specificback pain where a specific area of the back (e.g. the lumbar region) canbe targeted to give greater support are particularly helped by such asystem. By adjusting the mattress support to match a person's body shapeand weight distribution, further flexibility can be provided to theviscoelastic mattress without reducing the density of the foam core.

[0061] Another problem in the prior art concerns the tendency ofviscoelastic pillows to allow the head and neck to sag downward out ofalignment with the spine. This is true for the general population, aswell as neck patients under the care of a chiropractor or physicaltherapist. Many chiropractors have complained that the tendency of thesepillows to over-compress makes them undesirable. Not only do they nothelp maintain proper curvature of the cervical vertebrae followingchiropractic manipulations, but in many cases they exacerbate theproblem and contradict the treatments.

[0062] To address these problems, the inventors have developed a pillowthat combines the advantages of shape-conforming viscoelastic foam withstructure for increased support for the head and neck. As shown in FIGS.6 & 7, the pillow 60 comprises a body 62 of viscoelastic foam, with acontoured top 64 and a flat bottom 66. There are two ridges on thecontoured top—a larger ridge 68 a for lying on one's side, and a smallerridge 68 b for lying on one's back. Disposed in the bottom 66 of thepillow under and parallel to each ridge 68 are two insert pockets 70 a,70 b. Semicylindrical foam inserts 72 are configured to be inserted intothe insert pockets to increase the support provided by the ridges. Inone embodiment, the inserts are a half cylinder about 4 inches wide andabout 2 inches thick. However, the height and width of the inserts canvary depending upon the size of the pillow. The viscoelastic foam pillowbody and the inserts are surrounded by a cover 74 with an opening 76 toaccess the inserts.

[0063] The pillow body is preferably of the same 3510 viscoelastic foamdescribed above, and thus provides the same advantageoustemperature-related properties noted above. Consequently, the pillowbody will not harden to the same extent as other viscoelastic materialsat lower room temperatures. This can prevent excessive firmness incolder rooms, and thus prevent the creation of pressure points on theneck and possible neck pain. In one embodiment, the inserts 72 cancomprise cutouts of the viscoelastic foam that are created when theinsert pockets are cut out of the pillow body. Alternatively, theinserts can be of other materials, such as polyurethane foam, and canhave a density that is greater than that of the viscoelastic foam, so asto increase the desired level of support. Inserts in a variety ofdensities may be used to adjust the firmness of the ridges 68. Forexample, a soft insert having an indentation force deflection (IFD) of32±3 (i.e. IFD of 29-35) can be used. A medium insert having an IFD of85±5 can also be used. Finally, a firm insert with an IFD at or above120 can be used for greatest stiffness. Additionally, it will beapparent that the pillow could conceivably be used without any inserts,providing the softest possible configuration. The inserts are typicallymade of polyurethane foam, but can be any material with similarcompression properties.

[0064] The inserts 72 used in the pillow 60 limit the amount ofcompression in response to the weight of the neck and head, thus keepingthe head in proper alignment with the spine. Fine-tuning of the firmnessof the pillow is accomplished by selecting inserts with differentdensities. Unlike traditional foam core pillows that tend to be too firmand raise the head too far, the viscoelastic foam allows the head andneck to sink into alignment with the spine. However, the more denseinserts prevent the head from sinking too far on larger body builds, aswith other memory foam pillows and many feather pillows. Theseproperties allow optimal head-spine alignment, reducing neck discomfortand facilitating restful sleep. FIG. 8 shows how the smaller ridge 68 bwith the foam insert 72 assists in keeping the proper curvature of thespine 84 when lying on one's back. FIG. 9 shows how the larger ridge 68a with the foam insert 72 assists in keeping the spine straight whenlying on one's side.

[0065] It is to be understood that the above-described arrangements areonly illustrative of the application for the principles of the presentinvention. Numerous modifications and alternative arrangements can bedevised without departing from the spirit and scope of the presentinvention. Thus, while the present invention has been shown in thedrawings and fully described above with particularity and detail inconnection with what is presently deemed to be the most practical andpreferred embodiment(s) of the invention, it will be apparent to thoseof ordinary skill in the art that numerous modifications, including, butnot limited to, variation in size, materials, shape, form, function andmanner of operation, assembly and use may be made without departing fromthe principles and concepts set forth herein.

What is claimed is:
 1. A mattress system, comprising: A) a mattress,including (i) a core layer providing a base support; and (ii) a toplayer of viscoelastic foam, disposed atop the core layer, having adensity of from about 3.0 to about 4.5 lb/ft³.
 2. A mattress system inaccordance with claim 1, wherein the core layer comprises foam materialhaving a density of from about 2.0 to about 2.7 lb/ft³.
 3. A mattresssystem in accordance with claim 2, wherein the core layer has athickness of from about 3″ to about 7″.
 4. A mattress system inaccordance with claim 2, wherein the core layer of foam material isselected from the group consisting of polyurethane foam, latex foam anda combination of polyurethane foam and latex foam.
 5. A mattress systemin accordance with claim 1, wherein the top layer has a thickness offrom about 2″ to about 4″.
 6. A mattress system in accordance with claim1, wherein the top layer is attached to the core layer with a chemicaladhesive.
 7. A mattress system in accordance with claim 1, furthercomprising a removable cover surrounding the core layer and the toplayer.
 8. A mattress system in accordance with claim 1, wherein theviscoelastic foam layer is configured to provide a substantially uniformresponse over a room temperature range of from about 55° F. to about 85°F.
 9. A mattress system in accordance with claim 1, further comprising:B) a mattress support, configured to support the mattress, including:(i) a perimeter frame; (ii) a plurality of slats, spanning transverselyacross the perimeter frame and positioned to directly contact a bottomsurface of the mattress, including at least seven pairs of adjustableslats, each pair being positioned to support a specific area of a bodydisposed atop the mattress; (iii) a plurality of stiffener slats,spanning transversely across the perimeter frame, each stiffener slatbeing disposed beneath a corresponding pair of adjustable slats; and(iv) at least one moveable adjuster clip, interconnected between eachstiffener slat and the corresponding pair of adjustable slats,configured to be selectively moveable across the span of the slats, soas to adjust a relative flexural stiffness of the corresponding pair ofadjustable slats.
 10. A mattress system in accordance with claim 9,further comprising: (a) a center support, longitudinally bisecting theperimeter frame; and wherein (b) the plurality of slats comprises firstand second pluralities of slats transversely spanning between a side ofthe perimeter frame and the center support, each plurality of slatsincluding seven pairs of adjustable slats positioned to support aspecific area of a body disposed atop the mattress, seven stiffenerslats disposed beneath a corresponding pair of adjustable slats, and atleast one moveable adjuster clip, interconnected between each stiffenerslat and the corresponding pair of adjustable slats, configured to beselectively moveable across the span of the slats, so as to adjust therelative flexural stiffness of the corresponding pair of adjustableslats; so as to allow independent stiffness adjustment of the supportsystem on each side of the center support.
 11. A mattress system inaccordance with claim 9, wherein, at least one of the pairs ofadjustable slats is positioned to support a shoulder region of the bodydisposed atop the mattress.
 12. A mattress system in accordance withclaim 1, further comprising: C) a pillow, including (i) a body ofviscoelastic foam, having a contoured top side including a ridge, and abottom side with an insert pocket; and (ii) a foam insert, configured tobe inserted into the insert pocket so as to increase the stiffness ofthe pillow below the ridge.
 13. A mattress system in accordance withclaim 12, wherein the insert pocket comprises a first insert pocket anda second insert pocket, and the foam insert comprises two foam inserts.14. A mattress system in accordance with claim 13, wherein the contouredtop side further comprises: (a) a back support ridge, parallel to andabove the first insert pocket, to support a user's head and neck whenthe user is lying on the user's back; and (b) a side support ridge,parallel to and above the second insert pocket, to support the user'shead and neck when the user is lying on the user's side, whereby thefoam is prevented from collapsing, so that the user's neck will bebetter supported.
 15. A mattress system in accordance with claim 13,wherein the foam inserts comprise elongate pieces of polyurethane,having a semicylindrical cross-section.
 16. A mattress system inaccordance with claim 12, wherein the viscoelastic foam material of thebody is configured to provide a substantially uniform response over aroom temperature range of from about 55° F. to about 85° F.
 17. Amattress, comprising: a) a core layer of foam material, having a coredensity primarily configured to support a human body; b) a top layer ofviscoelastic foam, disposed atop the core layer, having a compositionthat maintains substantially uniform viscoelastic response over a roomtemperature range of from about 55° F. to about 85° F.
 18. A mattress inaccordance with claim 17, wherein the core layer has a density of fromabout 2.4 to 2.7 lb/ft³, and the top layer of viscoelastic foam has adensity of from about 3.0 to about 4 lb/ft³.
 19. A mattress inaccordance with claim 17, wherein the viscoelastic response of the toplayer varies by less than about 15% within a range from about 30° F. toabout 100° F.
 20. A pillow, comprising: a) a body of viscoelastic foam,having a contoured top side including a ridge, and a bottom side with atleast one insert pocket, the viscoelastic material being configured toprovide a substantially uniform viscoelastic response over a roomtemperature range of from about 55° F. to about 85° F.; b) a cover,surrounding the body, having an opening configured to allow access tothe at least one insert pocket; and c) at least one foam insert,configured to be inserted into the at least one insert pocket below theridge, and thereby increase the stiffness of the pillow below the ridge.